JPH0317443B2 - - Google Patents

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is used in a machine lifting device for agricultural machines such as rice transplanters and direct sowing machines, and in particular, the machine body is raised and lowered by vertical movement of wheels. The present invention relates to an agricultural machine configured to control the height of the machine by connecting a switching valve of a hydraulic cylinder to a machine height detection mechanism and a manual operation lever.

[Conventional technology]

Among the above-mentioned conventional agricultural working machines, it is generally known that the machine body is raised and lowered by using a body height detection mechanism installed between a float that slides on the rice field and a switching valve. .

[Problem that the invention seeks to solve]

For example, when a walking agricultural machine using the above-mentioned mechanism is moved around in a field, there is no device to stop and fix the rising machine at a certain desired height position, so the amount of rise of the machine changes each time it moves. It was difficult to maintain the aircraft at a constant desired height, making it difficult to rotate smoothly and making operations difficult.

The technical problem of the present invention is to provide a simple and inexpensive mechanism capable of quickly and accurately stopping and holding an aircraft during a lifting operation always at a preset height position.

[Means to solve the problem]

The technical measures taken by the present invention to solve the above problems are as follows.

In an agricultural machine configured to control the height of the machine body by connecting a switching valve of a hydraulic cylinder that raises and lowers the work machine by vertical movement of the wheels to a machine height detection mechanism and a manual operation lever,
A movable member that moves in conjunction with the lifting and lowering operation of the work machine and that engages the switching valve and switches the switching valve from the lifting operating position to the neutral position when switching the lifting machine is moved in conjunction with the lifting and lowering operation of the wheels. It is installed on a member that moves integrally, and when the aircraft is raised, the switching valve is forcibly switched to the neutral position by the movable member, giving priority to the aircraft height detection mechanism and manual operation lever, and the aircraft is set in advance. The device is characterized in that it is always set at a certain height position.

[Effect]

When the planting clutch lever is switched from the on position to the off position or up position, the plate directly connected to the switching valve of the hydraulic cylinder is switched to the aircraft lift position and the aircraft is raised, and the plate moves as the aircraft rises. A movable member engages the plate to force the switching valve from the aircraft raised position to the neutral position, and the aircraft is fixed in that position.

Embodiment Hereinafter, an embodiment of the present invention will be described using a rice transplanter as an example.

As shown in FIGS. 1 and 2, the rice transplanter 1 has a working body 5 consisting of an engine 2, a transmission case 3, etc. Below the working body 5, a float 6 is connected to a rear joint fulcrum 7. It is supported by a front link 8 and is swingably suspended.

A handle 9 extends from the rear of the machine body 5, and a seedling stand 10 is mounted along the handle 9 so as to be able to move back and forth from side to side. A planting rod 11 to which power is transmitted is provided.

Further, wheels 15 are disposed on the body 5 via a chain case 13 which is supported by a pivot shaft 12 so as to be swingable in the vertical direction. A bracket 13a that protrudes upward is fixed to the rotating base of the chain case 13, and a piston 16a of a hydraulic cylinder 16 fixed to the body is attached to the tip of the bracket 13a.
and is connected via a rod 13b. The hydraulic cylinder 16 communicates with a hydraulic pump 19 via a rotary type switching valve 17, and therefore, by operating the valve 17, the height of the machine relative to the wheels 15 can be changed.

A T-shaped plate 20 constituting a linkage device is fixed to the operation shaft 17a of the switching valve 17, and an engagement pin 21 is protruded from the upper end of the plate 20. A connecting pin 22 is provided protruding from the middle part of the plate 20, and a connecting pin 23 is provided protruding from the lower end of the plate 20, and the portion protruding laterally from the operating shaft 17a is A lug surface is formed by folding back into a letter shape, and a connecting pin 24 is protruded from the lug surface.
It is provided parallel to a.

The connecting pin 22 has a lower wire 32 connected to its terminal 3.
The elongated holes 32b provided in the springs 33a provided at the ends of the connecting pins 23 are fitted over the elongated holes 32b of the connecting pins 23, and the elongated holes 33b of the springs 33a provided at the ends of the raising wires 33 are fitted onto the connecting pins 23 to connect them.

On the other hand, a sensing rod 25 constituting a body height sensing mechanism is pivotally supported on the front link 8 portion of the float 6, and the other end of the rod 25 is connected to an arm 26. The arm 26 is rotatably supported by a fixed shaft 27 fixed to the work machine 5, and the shaft 27 has an intermediate arm 2 having a bending engagement portion 28a.
The arm 28 rotates together with the arm 26 when the arm 26 rotates upward, that is, counterclockwise, by the engagement of the bent engagement portion 28a.
29 is a spring provided between the intermediate arm 28 and the working machine 5, and the bending engagement portion 28a is connected to the arm 26.
The intermediate arm 28 is biased clockwise so as to engage with the float 6 and apply a predetermined grounding pressure to the float 6.

Also, a pin 28b provided at one end of the intermediate arm 28
A link 30 is passed between the connecting pin 24 of the plate 20, and both pins 28b and 24 fit into long holes 30a and 30b provided at both ends of the link 30, and are connected by a weak spring 31. It is.

On the other hand, the main clutch lever 42 and the planting clutch lever 43 are respectively guided by guide grooves 35a and 35b of a lever guide plate 35 provided on the handle 9, and both levers 42 and 43 are rotatably attached to the support shaft 36. It is pivoted. The main clutch lever 42 is connected to one end of the lowering wire 32 and one end of a wire connected to the main clutch, and the planting clutch lever 43 is connected to the raising wire 33.
and one end of a wire that connects to the planting clutch.

The guide groove 35 of the main clutch lever 42
In Figure a, the clutch is connected in the upper engaged position, disconnected in the middle disengaged position, and the aircraft descends with the clutch disengaged in the lower lower position. In addition, in the guide groove 35b of the planting clutch lever 43, the clutch is connected at the upper engaged position, disconnected at the middle disengaged position, and the upper position of the lower stage indicates that the aircraft will rise with the clutch disengaged. It is marked.

When the plate 20 fixed to the operating shaft 17a is in the upright state N as shown in FIG. 4, the hydraulic cylinder 16 becomes neutral and the vertical movement of the aircraft is fixed, and the switching valve 17 is tilted forward clockwise to the U position. When this happens, the aircraft rises, tilts backwards counterclockwise, and
The aircraft is configured to descend when it reaches this position.

When the main clutch lever 42 is in the engaged position, the connecting pin 22 of the plate 20, which is in the neutral position N, is located at the center of the long hole 32b of the lowering wire 32, and in the disengaged position, the connecting pin 22 of the plate 20 is in contact with the outer end of the long hole 32b. Once in this position, the plate 20 is rotated counterclockwise and moved to the lowered position D.

When the planting clutch 43 is in the engaged position, the connecting pin 23 of the plate 20 is located at the center of the elongated hole 33b of the raising wire 33, and when it is in the off position, it contacts the outer end of the elongated hole 33b, and when it is in the upper position, the connecting pin 23 of the plate 20 is located at the center of the elongated hole 33b. It is designed to be rotated in the direction and moved to the raised position U.

Reference numeral 37 denotes a movable member provided above the base of the chain case 13, which moves as the working machine 5 moves up and down, and engages with the switching valve 17 when switching the machine up to move the switching valve 17 to the machine up operation position U. The bracket 13a of the chain case 13 has a base that can be switched from
The movable member 37 is pivoted in the longitudinal direction of the fuselage, and its tip is opposed to the engagement pin 21 of the plate 20. When the movable member 37 is rotated counterclockwise about the pivot 38, It is arranged to be close to the engagement pin 20. A return spring 37a is provided between the movable member 37 and the bracket 13a, and the movable member 37 is biased clockwise (towards the front of the machine body).

Reference numeral 39 denotes a body height adjustment lever connected to the movable member 37 via a wire 40, the base of which is rotatably supported on an extension of the support shaft 36 provided on the lever guide plate 35, and 41, and is fitted in the guide hole 41a in a freely adjustable and fixed manner. When the lever 39 is operated in the L direction in FIGS. 1 and 7, the distance between the tip of the movable member 37 and the engagement pin 21 is narrowed, and when the lever 39 is operated in the H direction, the distance is widened. Therefore, if the body height adjustment lever 39 is set, for example, to the L side, the movable member 37 will come into contact with and press the engagement pin 21 of the plate 20 when the body is raised, and the plate 20 will be at the neutral position N.
The timing for moving the lever 39 to the H side becomes earlier, and the height when the aircraft ascends is determined to be lower. Conversely, if the lever 39 is set to the H side, the timing is delayed, and the height when the aircraft ascends is determined by that amount. It is configured so that the height is set at a high position.

The present invention is configured as described above, and the rice transplanter 1
To perform planting work, move the machine height adjustment lever 39 in advance according to the plowing depth S of the field. For example, if it is shallow, move it to the L side, and conversely, if it is deep, move it to the H side.
Set it on the side. Then, when the main clutch lever 42 is switched from the disengaged position to the engaged position and the planting clutch lever 43 is switched from the disengaged position to the engaged position to connect each clutch, the wheels 15 rotate and the machine runs, and the planting rod 11 is rotated to perform the planting work.

At that time, the plate 20 is in the neutral (N position) state, and the connecting pins 22 and 23 are in the center of the long holes 32b and 33b, respectively, so that the plate 20 is in the neutral (N position) state.
The plate 2 is rotatable in the clockwise and counterclockwise directions in the range of 2b and 33b, and follows the vertical movement of the float 6 that occurs as the depth S of the tiller changes.
0 rotates to switch the switching valve 17 between forward and reverse to operate the hydraulic cylinder 16, and the height of the machine is set to the plowing depth S.
It is in an automatic control state where it is automatically controlled in response to. For example, when the plowing depth S becomes deeper and the machine descends, a large field pressure acts on the float 6.
The arm 26 is rotated counterclockwise via the sensing rod 25, the intermediate arm 28 is integrally rotated in the same direction via the engaging portion 28a, and the pin is rotated via the spring 31 by the rotation of the pin 28b. 28b The plate 20 is rotated clockwise while the connecting pin 24 is held at the inner ends of the elongated holes 30a and 30b.
As a result, the switching valve 17 is switched to the raised position U, and due to the extension of the piston 16a of the hydraulic cylinder 16, the chain case 13 is moved through the rod 13b.
rotates counterclockwise, and the wheels 15 move downward. Therefore, when the working body 5 rises and the field pressure acting on the float 6 decreases to reach the appropriate height position, the plate 20 is moved to the neutral position N by the movable member 37.
will be returned to.

Conversely, when the plowing depth S becomes shallow, the height of the machine is automatically controlled by the opposite effect to the above.

When rotating, the planting clutch lever 43 is switched from the engaged position to the off position or the upper position while leaving the main clutch lever 42 in the engaged position. For example, when the planting clutch is switched to the upper position, the planting clutch is disconnected, and at the same time, the connecting pin 23 is pulled at the outer end of the elongated hole 33b of the raising wire 33, and the plate 20 is rotated clockwise as shown in FIG. position (at this time, the connecting pin 22 moves from the center to the outer end of the elongated hole 32b), the switching valve 17 switches to extend the hydraulic cylinder 16, and the wheels 15 descend and the work machine 5 rises. Along with this, the movable member 37
rotates counterclockwise around the wheel 12, and its tip contacts and presses the engagement pin 21,
As shown in FIG. 6, the plate 20 is moved to the neutral position N (at this time, the spring 33a is extended).
Then, the switching valve 17 is switched to the neutral position, the extension of the hydraulic cylinder 16 is stopped, and the work machine 5 is held fixed at that height position. (At this time, the counterclockwise rotation of the plate 20 due to the descending force of the float 6 is prevented by the spring 33a.) The height of the aircraft during the above rotation does not change each time it rotates, but is always kept at a constant predetermined height. Since it is held at the same height, turning operations can be performed extremely smoothly.

If you want to plant again after completing the rotation, you can simply switch the planting clutch lever 43 from the upper position to the on position. will descend to the appropriate height, and planting will resume in that state.

Furthermore, the aircraft can be raised and rotated by using the sensing device of the float 6 as in the past.
That is, in that case, when the planting clutch lever 43 is switched to the off position and the handle 9 is lifted upward, the float 6 comes into pressure contact with the field surface, and the distance between the front part of the float 6 and the working machine 5 becomes narrower, and the above-mentioned machine An automatic control action in the upward direction operates, that is, the plate 20 rotates clockwise via the sensing rod 25, the arm 26, the intermediate arm 28 and the link 30, switches the switching valve 17, extends the hydraulic cylinder 16, and moves the wheel. 15 is lowered and the working machine 5 is raised. When the machine rises by an appropriate amount, the movable member 37 contacts and presses the engagement pin 21 as described above, and the plate 2
0 moves to the neutral position N, which allows the aircraft to be held at a desired height position and rotate.

When setting the machine height adjustment lever 39 in advance to correspond to the plowing depth S, it is sufficient that the distance between the float 6 and the field surface during rotation is the minimum necessary. Regardless of whether the distance is deep or shallow, the body height adjustment lever 39 may be set so that this distance is a substantially constant minimum value.

In this way, for example, if the plowing depth S is shallow, the height of the machine during rotation is kept relatively low without increasing it unnecessarily, and the vertical movement of the machine can be performed efficiently at an early timing. Furthermore, even when the plowing depth S is deep, a minimum necessary distance is provided between the float 6 and the field surface, and smooth and efficient movement can be achieved.

The movable member 37 may be adjustably fixed to the bracket 13a with a bolt 47 by providing a long hole 46 as in the other embodiment shown in FIG.

〔Effect of the invention〕

In particular, the present invention provides a movable member that automatically moves as the work machine moves up and down, and this member engages with a switching valve of a hydraulic cylinder to forcibly switch the work machine from a lift operation position to a neutral position. This allows the aircraft to be quickly and accurately maintained at a constant, preset desired height position after it has been raised. For example, when the aircraft is making a turn, the rising height changes each time it goes around. By setting the height to the minimum required height, smooth and quick movement is possible, and operation becomes easy.

Furthermore, since the switching operation is performed using the movement of the wheel lifting mechanism itself, the structure is simple and can be constructed at low cost.

Furthermore, when the movable member is configured to be adjustable in position at the operating position in accordance with the depth of the plow as in the embodiment of the present invention, the timing of engagement between the movable member and the switching valve can be selectively varied, and the field It is possible to obtain the most appropriate height of rise for the conditions.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a partial explanatory diagram showing the main parts, FIG. 2 is a side view of a rice transplanter applicable to the present invention, and FIG. A front sectional view, FIG. 4 is an enlarged side view of the connecting part of the switching valve, FIGS. 5 and 6 are explanatory views of its operation, FIG. 7 is a perspective view showing the lever mounting part, The figure shows another embodiment. 5... Working machine, 16... Hydraulic cylinder, 1
7...Switching valve, 20...Plate, 25...
Sensing rod, 37... Movable member, 39... Airframe height adjustment lever, 42... Main clutch lever, 43
...Planting clutch lever.

Claims (1)

[Scope of Claims] 1. A switching valve of a hydraulic cylinder that raises and lowers the work machine by vertical movement of the wheels is connected to a machine height detection mechanism and a manual operation lever to control the height of the machine. In the agricultural machine, it moves in conjunction with the lifting and lowering operation of the working machine,
In addition, a movable member that engages with the switching valve and switches the switching valve from the aircraft lifting operation position to the neutral position when switching the aircraft upward is provided on a member that moves integrally with the vertical movement of the wheels, and when the aircraft is raised. The switching valve is configured to be forcibly switched to the neutral position by the movable member, giving priority to the operation of the aircraft height detection mechanism and the manual operation lever, so that the aircraft is always set at a preset height position. A machine body lifting device for an agricultural machine characterized by the following. 2. A body lifting device for an agricultural machine according to claim 1, wherein the movable member is configured to be position adjustable, and the timing of engagement between the movable member and the switching valve is selectively variable.